You can use fresh or frozen blueberries in this recipe. The batter is fairly thick, so the berries could get crushed – although I don’t have a problem with that! I quite like the burst of flavour from the whole berries, and the spread of juiciness you get as a result of some of them breaking up in the mixture. Blueberries contain a pigment that causes them to bleed out their colour, and that’s why we add them last into the batter.